feat(agent): Voll-Audit-Link in die Snapshot-Detail-Seite

Der "Voll-Audit öffnen (alle MCs)"-Link hing in ComplianceResultTabs (aus
der Agent-Seite entfernt). Jetzt im Detail-Header der Snapshot-Ansicht via
snap.check_id → /sdk/agent/audit/{check_id} (Audit-Daten verifiziert
vorhanden). Plus Site-Titel-Header.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

admin-compliance/app/sdk/agent/snapshots/[snapshotId]/page.tsx

@@ -88,6 +88,28 @@ export default function SnapshotDetail(
         </div>
       ) : (
         <>
+          <div className="flex items-center justify-between gap-3 flex-wrap">
+            <div>
+              <h1 className="text-lg font-semibold text-gray-900">
+                {snap.site_label || snap.site_domain || 'Snapshot'}
+              </h1>
+              <p className="text-xs text-gray-500">
+                {snap.site_domain}
+                {snap.created_at ? ` · ${String(snap.created_at).slice(0, 16).replace('T', ' ')}` : ''}
+              </p>
+            </div>
+            {snap.check_id && (
+              <a
+                href={`/sdk/agent/audit/${snap.check_id}`}
+                target="_blank"
+                rel="noopener"
+                className="px-3 py-1.5 text-sm rounded-lg border border-blue-200 text-blue-700 hover:bg-blue-50 whitespace-nowrap"
+              >
+                Voll-Audit öffnen (alle MCs) →
+              </a>
+            )}
+          </div>
+
           <div className="flex gap-1 border-b border-gray-200">
             {modules.map(m => tabBtn(m.key, m.label))}
           </div>